The research within this Section concentrates on the utilization of the unique properties of the X-ray radiation generated at the synchrotron and in particular at very intense undulator beam lines of the Advanced Photon Source (APS) at the Argonne National Laboratory, where we are located. The two most important characteristics of synchrotron radiation are the high intensity of the X-ray beam and the tunability of the wavelength; both of these properties are utilized in the research investigations within the Section. In addition to conducting research investigations, the Section personnel provides technological and scientific support for NIH researchers collecting diffraction data at APS.